Where are IPO curves and deltas?
The online manual states that "In Blender 2.5, IPO Curves have been replaced by FCurves, however, editing these curves is essentially still the same."
https://www.blender.org/manual/animation/editors/graph/fcurves.html

I'll dig more for "deltas" info.
[edit] see this thread an BA it may help you: http://blenderartists.org/forum/showthread.php?219126-Move-Existing-f-Curve-to-delta-equivalent [/edit]

I discovered there is an option "Animated Transforms to Deltas" available through the space bar command search tool, it should derive by this GSoc work http://aligorith.blogspot.it/2011/05/gsoc11-greeting-goodies.html (this is what the last comment in the above cited BA thread refers to)